G-men grab a gangster and a governor thanks to a clerk in the fingerprints division.

During World War II, an American bomber pilot is rescued after drifting at sea aboard a raft. After being administered truth serum, he tells the doctor a story of how he and the three survivors of his plane crash washed up on an island that was inhabited by a tribe of beautiful primitive cave-women, dinosaurs and a group of savage cavemen who are bent on abducting the women for breeding purposes.

Filmed with the full cooperation of the U.S. Army, Breakthrough is a lean, no-nonsense war film set during the 1944 invasion of the continent.